Option 16 (vendor-class) in DHCPv6

[Mirko Vogt]

Hello!

I'm currently trying to setup my ISC DHCP client to send a
vendor-identifier string in its dhcpv6 solicite message (Option 16).
After some sniffing and wondering why I can't find anything about Option
16 within the captured traffic snippets and its value I put into my
dhclient file, I scrolled over the source code and found these lines in
"tables.c":

#if 0
  /* XXX: user-class contents are of the form "StA" where the
   * integer describes the length of the text field.  We don't have
   * an atom for pre-determined-length octet strings yet, so we
   * can't quite do these two.
   */
#if 0
  { "user-class", "X",		&dhcpv6_universe, 15, 1 },
  { "vendor-class", "X",	&dhcpv6_universe, 16, 1 },
#endif

As far as I understand the comment, there's prerequisites missing for
being able to implement/use those options - however I don't understand
the real technical cause for this, so please don't get me wrong if I ask:
What's so hard getting Option 16 (and apparently 15 as well) implemented
and supported? Isn't Option 16 just a field as is Option 60 in DHCPv4?
Could anybody elaborate above mentioned comment in the source code?

Thanks a lot in advance!

Cheers

  mirko